Four Wallabies – David Pocock, Matt Toomua, Matt Giteau and Will Genia – have shaved their heads in a show of support for ACT Brumbies captain Lealiifano as he undergoes chemotherapy.

Lealiifano was diagnosed with leukaemia two weeks ago and will remain in hospital until next month as part of his treatment.

The respected Brumbies leader has been inundated with support from around the world but the tribute by the Wallabies quartet is a massive nod of respect on the eve of their battle against the All Blacks.

The Wallabies are trying to end a 13-year Bledisloe Cup losing streak in the series-opener at ANZ Stadium.

Pocock, Giteau and Genia are in the starting XV, while Toomua will come off the bench as the back-up playmaker.

"He's one of us, he's one of the boys so he's in our thoughts, in our prayers," Genia said.

"He's a good bloke so the guys will definitely have him in our thoughts when we get out there on Saturday."

Wallabies coach Michael Cheika has overhauled his Test line-up after a 3-0 series loss to England in June.

Brumbies prop Allan Alaalatoa will make his debut from the bench, while Pocock reverts to the No.8 role in an openside flanker double act with Michael Hooper.

Hardworking Brumbies back-rower Scott Fardy has been moved to the Wallabies bench for the first time since 2013 as Cheika shakes up his side.

Fardy was one of the Wallabies' most consistent performers against England and has started in 32 of his 33 Tests for Australia, but Cheika has opted to promote Ben McCalman to the No.6 job.

"I don't think it's a straight comparison like that," Cheika said.

"Fards has been in the team for a fair while now and Ben's been putting pressure on at different times and every time he steps out to play for Australia.

"We've been working on a few things there and he's [McCalman] shown his quality there and we know that New Zealand are the best lineout defenders in the game.

"We're going to have to be on our money tactically in what we do there and each one in his role, Ben included, when the game's on and the heat of battle, really clear on what their job is inside of our lineout."

Toomua moves back to the bench after playing a starring role in the last Test against England, with Giteau to resume the inside centre position.

Toomua was one of the Wallabies players who broke from camp last week to drive from the Central Coast to Canberra to visit Lealiifano in hospital.

The Wallabies will roll out 13 players from the starting XV from the World Cup final almost 12 months ago when the All Blacks beat Australia 34-17.

In contrast, the All Blacks have lost retired stars Dan Carter, Richie McCaw, Keven Mealamu, Tony Woodcock, Conrad Smith and Ma'a Nonu.

Cheika backed Genia to slot into the Wallabies starting side and renew his partnership with Bernard Foley, despite only playing a handful of games since the World Cup final.

"He's worked very hard from a fitness point of view I know since he's come back," Cheika said.

"Of course, nothing simulates the game like the game itself but he's got plenty of experience to know how to manage himself in a game and when to take advantage of the situations that are there and experience in the halves is very, very important."

BLEDISLOE CUP

Saturday: Australia v New Zealand at ANZ Stadium, 8.05pm.

Wallabies team: 1. Scott Sio, 2. Stephen Moore, 3. Sekope Kepu, 4.Kane Douglas, 5. Rob Simmons, 6. Ben McCalman, 7. Michael Hooper, 8. David Pocock, 9. Will Genia, 10. Bernard Foley, 11. Dane Haylett-Petty, 12. Matt Giteau, 13. Tevita Kuridrani, 14. Adam Ashley-Cooper, 15. Israel Folau. Reserves: 16. Tatafu Polota-Nau, 17. James Slipper, 18. Allan Alaalatoa, 19. Dean Mumm, 20. Scott Fardy, 21. Nick Phipps, 22. Matt Toomua, 23. Rob Horne.